Faculty Bibliography

As multiple myeloma (MM) treatments evolve, frequent updates are required to monitor the long-term effect of changes in approach. Traditionally, MM is considered an incurable disease, with most patients eventually relapsing. However, improvements in treatments has raised the possibility that MM might be functionally curable. To examine improvements in long-term survival, we followed 4329 patients with newly diagnosed MM treated with autologous stem cell transplantation (ASCT) at the University of Arkansas for Medical Sciences from 1989 through 2018. Overall survival (OS) and progression-free survival (PFS) were evaluated using Kaplan-Meier analysis, Cox proportional hazards models, relative survival analysis, and cure modeling among different time periods, risk groups, and demographic traits. Steady improvements in OS were found, with patients treated in 2014 or later having superior OS (hazard ratio, 0.35; 95% confidence interval [CI], 0.27-0.45) and reduced excess risk for MM death (relative excess risk, 0.30; 95% CI, 0.22-0.41) compared with patients treated in 1997 or earlier. Patients treated during intervening time periods often had intermediate survival, but trends in OS, PFS, and landmarked analyses were inconsistent. Cure models support the potential for cure, ranging from 6.3% to 31.3%, depending on the year of treatment, with 10.0% to 18.6% of patients achieving their normal life expectancy across multiple periods. There was some evidence of reductions in early mortality within 3 years of diagnosis, longer complete response (CR) duration, and reductions in relapse after achieving CR. However, results differed depending on age, risk group, and cytogenetic characteristics.

BACKGROUND:Multiple myeloma has been shown to have substantial clonal heterogeneity, suggesting that agents with different mechanisms of action might be required to induce deep responses and improve outcomes. Such agents could be given in combination or in sequence on the basis of previous response. We aimed to assess the clinical value of maximising responses by using therapeutic agents with different modes of action, the use of which is directed by the response to the initial combination therapy. We aimed to assess response-adapted intensification treatment with cyclophosphamide, bortezomib, and dexamethasone (CVD) versus no intensification treatment in patients with newly diagnosed multiple myeloma who had a suboptimal response to initial immunomodulatory triplet treatment which was standard of care in the UK at the time of trial design. METHODS:subcutaneously or intravenously on days 1, 4, 8, and 11), and dexamethasone (20 mg daily orally on days 1, 2, 4, 5, 8, 9, 11, and 12) up to a maximum of eight cycles of 21 days or no treatment. Patients were stratified by allocated induction treatment, response to induction treatment, and centre. The co-primary endpoints were progression-free survival and overall survival, assessed from intensification randomisation to data cutoff, analysed by intention to treat. Safety analysis was per protocol. This study is registered with the ISRCTN registry, number ISRCTN49407852, and clinicaltrialsregister.eu, number 2009-010956-93, and has completed recruitment. FINDINGS/RESULTS:Between Nov 15, 2010, and July 28, 2016, 583 patients were enrolled to the intensification randomisation, representing 48% of the 1217 patients who achieved partial or minimal response after initial induction therapy. 289 patients were assigned to CVD treatment and 294 patients to no treatment. After a median follow-up of 29·7 months (IQR 17·0-43·5), median progression-free survival was 30 months (95% CI 25-36) with CVD and 20 months (15-28) with no CVD (hazard ratio [HR] 0·60, 95% CI 0·48-0·75, p<0·0001), and 3-year overall survival was 77·3% (95% Cl 71·0-83·5) in the CVD group and 78·5% (72·3-84·6) in the no CVD group (HR 0·98, 95% CI 0·67-1·43, p=0·93). The most common grade 3 or 4 adverse events for patients taking CVD were haematological, including neutropenia (18 [7%] patients), thrombocytopenia (19 [7%] patients), and anaemia (8 [3%] patients). No deaths in the CVD group were deemed treatment related. INTERPRETATION/CONCLUSIONS:Intensification treatment with CVD significantly improved progression-free survival in patients with newly diagnosed multiple myeloma and a suboptimal response to immunomodulatory induction therapy compared with no intensification treatment, but did not improve overall survival. The manageable safety profile of this combination and the encouraging results support further investigation of response-adapted approaches in this setting. The substantial number of patients not entering this trial randomisation following induction therapy, however, might support the use of combination therapies upfront to maximise response and improve outcomes as is now the standard of care in the UK. FUNDING/BACKGROUND:Cancer Research UK, Celgene, Amgen, Merck, Myeloma UK.

Background: Structural variants are key recurrent molecular features of myeloma (MM) with two types of complex rearrangement, chromoplexy and chromothripsis, having been described recently. The contribution of these to MM prognosis, rapid changes in clinical behavior and punctuated evolution is currently unknown as is the mechanism by which they deregulate gene function. XXMethod(s): We analyzed two sets of newly diagnosed MM data: 85 cases with phased whole genome sequencing; and 812 cases from CoMMpass where long-insert whole-genome sequencing was available. Patient derived xenografts from five MM cases were used to generate epigenetic maps for the histone marks, BRD4, MED1, H3K27Ac, H3K4me1, H3K4me3, H3K9me3, H3K36me3 and H3K27me3. XXResult(s): In the 10X data the median number of structural events per case was 25 (range 1 - 182); with a median of 14 intra-chromosomal events (range 1 - 179; P<0.001) and 7 inter-chromosomal events (range 0 - 29). Structural events were seen most frequently on chromosomes 14 (64%), 8 (53%), 1 (44%) and 6 (42%). Complex chromosomal rearrangements involving 3 or more chromosomal sites were seen in 46%, 4 or more sites in 20%, 5 or more in 10% and 6 or more in 5% of samples. There were significantly more structural events in the t(4;14) subgroup compared to the t(11;14) subgroup. Significantly more events were also seen in the bi-allelically inactivated TP53 cases. Using an elbow test defined cutoff, we identified cases with high structural variant load in 10% of cases. Chromoplexy called by "Chainfinder" was seen in 18% of cases. Chromothripsis called by "Shatterseek" was seen in 9% of cases. Cases with a high structural load alone were not associated with an adverse outcome whereas cases with chromoplexy or chromothripsis were associated with adverse PFS and OS, p=0.001. A new high-risk subgroup comprising approximately 5% of cases was identified with chromoplexy, chromothripsis and a high structural load. Gene set enrichment analysis of cases with chromoplexy and chromothripsis showed an excess of MYC, E2F and G2M targets, and a reduction in RAS signaling. Interferon a and g responses, an excess of TP53 and reduction in TRAF3 mutations was associated predominantly with chromothripsis. How chromoplexy and chromothripsis are tolerated by the cell is unknown and the association with the cGAS/STING response is further being explored. To determine how chromoplexy may deregulate multiple genes we identified the full spectrum of structural variants to the immunoglobulin (Ig) and non-Ig loci. A range of genes are deregulated by Ig loci including MAP3K14 at a frequency of 2% confirming the importance of non-canonical NFkB signaling. A novel intra-chromosomal rearrangement to ZFP36L1 was upregulated in 10% of cases but was not prognostic. Gene upregulation by non-Ig super enhancers is frequent and targets include PAX5, GLI3, CD40, NFKB1, MAP3K14, LRRC37A, LIPG, PHLDA3, ZNF267, CENPF, SLC44A2, MIER1, SOX30, TMEM258, PPIL1, and BUB3. The topologically associating domain (TADs) containing super enhancers bringing about gene deregulation include TXNDC5, FOXO3, FCHSD2, SP2, FAM46C, CACNA1C, TLCD2 and PIK3C2G. These super enhancers frequently contain important MM genes, the coding sequence of which are disrupted by the rearrangement and could contribute to the clinical phenotype. Accurately reconstructing the structure of the complex rearrangements will allow us to identify the mechanism of gene deregulation and to distinguish between either gene stacking, receptor stacking or both. XXConclusion(s): Upregulation of gene expression by super enhancer rearrangement is a major mechanism of gene deregulation in MM and complex structural events contribute significantly to adverse prognosis by a range of mechanisms as well as simple gene overexpression. Disclosures: Boyle: Amgen, Abbvie, Janssen, Takeda, Celgene Corporation: Honoraria; Amgen, Janssen, Takeda, Celgene Corporation: Other: Travel expenses. Walker: Celgene: Research Funding. Thakurta: Celgene: Employment, Equity Ownership. Flynt: Celgene Corporation: Employment, Equity Ownership. Davies: Amgen, Celgene, Janssen, Oncopeptides, Roche, Takeda: Membership on an entity's Board of Directors or advisory committees, Other: Consultant/Advisor; Janssen, Celgene: Other: Research Grant, Research Funding. Morgan: Amgen, Roche, Abbvie, Takeda, Celgene, Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Other: research grant, Research Funding.XXCopyright

MRD is a powerful predictor of survival outcomes in multiple myeloma but treatment regimens show increasing duration and complexity for both TE and TNE populations. For this reason, sequential assessments are preferable to single timepoints. This has been evaluated in the Myeloma XI trial, which was a phase 3 trial with three potential randomisations to determine induction therapy, consolidation therapy and maintenance in both TE and TNE patients. Bone marrow aspirates were obtained after induction, post consolidation (if given), post ASCT for TE patients and 6 months post maintenance randomisation. MRD was assessed using flow cytometry (minimum sensitivity 0.004%). This analysis represents a subset of 1630 samples that represent all patient groups and therapeutic timepoints. Overall MRD-negativity post-induction was 164/722 (22.7%). 70.1% of patients randomised to CCRD were MRD-negative compared to 19.6% after CTD or RCD in TE patients and 12.7% after CTDa and 19.2% after RCDa (p <0.001) in TNE patients. Levels of residual disease in MRD-positive patients were lower following CCRD induction; median 0.08% of leucocytes (range 0.001-9.5%), compared to medians of 0.31%, 0.23%, 0.38% and 0.42% following CTD, RCD, CTDa and RCDa respectively. MRD-negativity was demonstrated in 16/54 (29.7%) of patients who received bortezimib-based consolidation following a suboptimal response to induction. Post ASCT, 257/413 (62%) of samples were MRD-negative, with a significant increase in MRD-negativity rate relative to post induction seen with CTD (59.2% vs 19.6% post induction) and RCD (53.6% vs to 19.6% post induction). The level of conversion from MRD-positive post induction to MRD-negative post-ASCT was lower in the CCRD cohort (83.3% MRD-negative post ASCT compared to 70.1% following induction). Amongst the patients who underwent maintenance randomisation, MRD-negativity was demonstrated in 238/413 (57.6%). Conversion to MRD-negativity was seen in 32% of MRD-positive patients on lenalidomide maintenance, whilst those patients who became MRD-positive during maintenance had poor outcome. For those patients that remained MRD-positive, lower levels of residual disease were noted in those receiving maintenance (median 0.15% on maintenance vs 0.39%, p=0.04). Sequential MRD monitoring allows for the assessment of individual components of complex myeloma therapeutic strategies. It enables comparison of induction regimens, possibly identifying patients that may not require ASCT. Consolidation or maintenance strategies can also be assessed. This data suggests a potential future role for flow cytometric MRD assessment in individual patient management. A full dataset of >4000 samples and mature outcome data will be presented at the meeting. Keywords: Flow Cytometry Minimal residual disease Tracks: Myeloma Response Assessment including MRD
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Background: Multiple myeloma (MM) is a heterogeneous disease with variable outcomes. In the past several years, serum proteins, cytogenetics and gene expression profiling (GEP) have been used to predict outcomes of MM patients. Patients identified by the prognostic GEP70 gene signature as high risk (HR) have more aggressive disease and shorter survival compared to patients identified as low risk (LR). We have analyzed cfDNA levels in LR and HR patients and determined its correlation to GEP70 risk score. In a subset of patients, we performed low-pass whole genome sequencing (LP-WGS) and targeted sequencing to determine genomic alterations in cfDNA.
Method(s): GEP was performed on CD138+ plasma cells from bone marrow using Affymetrix U133 Plus 2.0 arrays. Low-risk (n=38) and high-risk MM patients (n=44) as determined by GEP70 score were selected. Plasma cells in bone marrow aspirate were ascertained for tumor burden by flow cytometry. cfDNA was extracted from plasma using QIAamp circulating nucleic acid kit (Qiagen) and was measured using Qubit fluorometer. In a subset of patients, plasma cfDNA, matched tumor DNA and matched white blood cell genomic DNA were sequenced using a targeted panel covering key driver genes and immunoglobulin regions involved in translocations in myeloma. Targeted sequencing was performed on NextSeq500 (Illumina) to a depth of 400-600x. LP-WGS was performed at 0.1X coverage. Sequencing data were analyzed using Strelka and ichor.
Result(s): Total cfDNA (ng/ml plasma) was significantly higher in the HR group compared to the LR group, median cfDNA LR=18.76 ng/ml range 0.2-140 ng/ml plasma vs. HR=33 ng/ml plasma range 7.3-726.66 ng/ml; p=0.02. cfDNA levels among different GEP subgroups did not reach significance, however patients in the PR subgroup had higher cfDNA in plasma compared to other subgroups. Ranked cfDNA levels correlated with GEP risk score r=0.32, p=0.0029 (Spearman's test). cfDNA levels also correlated with tumor burden r=0.41, p<0.0001 (Pearson's test). Additionally, LP-WGS analysis performed in a subset of patients showed that circulating tumor DNA (ctDNA) fraction correlated strongly with GEP70 risk score (Spearman r=0.83, p=0.0012). Monitoring of cfDNA levels in patients before and after chemotherapy showed an increase in cfDNA levels between 3-5 days after chemotherapy and fell to baseline levels a week later. Variant allele frequencies of NRAS and KRAS mutations were higher immediately post-chemotherapy compared to baseline in 3/4 patients.
Conclusion(s): cfDNA levels correlate with GEP70 risk score. In the small subset of sequenced patients, ctDNA fraction also correlated with GEP70 risk score. Molecular monitoring of myeloma using cfDNA can capture the mutational landscape in myeloma and can be a potential prognostic biomarker for MM disease. Keywords: cell-free DNA Gene expression profiling Whole genome sequencing Tracks: Multiple Myeloma Genomics
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Background: Multiple myeloma (MM) has significant spatial and temporal clonal heterogeneity suggesting therapeutic agents with different mechanisms of action, delivered in combination or sequentially, are required to maximize the depth of response and improve outcomes. The UK NCRI Myeloma XI phase III randomized trial compared induction with the second generation proteasome inhibitor carfilzomib and lenalidomide containing quadruplet, KCRD, vs a response-adapted approach of sequential triplet therapies in newly diagnosed transplant eligible patients.
Method(s): 1056 patients were randomized between KCRD (28 day cycles of carfilzomib (K) 36mg/m2 IV d1-2,8-9,15-16, cyclophosphamide (C) 500mg PO d1,8, lenalidomide (R) 25mg PO d1-21, dexamethasone (D) 40mg PO d1-4,8-9,15-16) and immunomodulatory drug (IMiD) triplet CTD/CRD prior to ASCT. Patients with a suboptimal response to CTD/CRD underwent response-adapted intensification randomization to a proteasome inhibitor (bortezomib, CVD) containing triplet or no CVD. A maintenance randomization at 3 months post ASCT compared lenalidomide to observation. Molecular high-risk (HiR) was classified by t(4;14), t(14;16), t(14;20), del(17p) or gain(1q) with ultra-high risk (UHiR) the presence of >1 lesions.
Result(s): KCRD was associated with a significantly longer PFS than IMiD triplet therapy (HR 0.63, 95%CI 0.51, 0.76, 3yr PFS KCRD 64.5% vs CTD/CRD 50.3%, p<0.0001). PFS2 was also significantly improved with KCRD (HR 0.75, 95% CI 0.56, 0.99, 3yr PFS2 KCRD 81.8% vs CTD/CRD 75.1%). Deeper response rates were seen in patients treated with KCRD vs CTD/CRD pre and post-transplant (p<0.0001). All regimens were well tolerated with no significant additional toxicity due to the quadruplet regimen. A higher proportion of patients receiving KCRD induction were able to undergo ASCT than those who received response-adapted induction and in an analysis restricted to those who had completed ASCT, KCRD induction was still associated with a significantly longer PFS. There was no significant heterogeneity in PFS outcome between molecular risk groups with a benefit for KCRD over triplets in all. In patients receiving KCRD there was no difference in response rate at the end of initial induction by risk group but UHiR disease was associated with significantly shorter PFS than both SR and HiR, whilst there was no difference in outcome between patients with HiR (one adverse lesion only) and SR. An exploratory analysis compared the patients receiving KCRD to patients in the CTD/CRD arm who had received the optimum response-adapted approach (i.e. excluding those with a suboptimal response randomized to no CVD). KCRD was associated with significantly longer PFS than using a response adapted sequential triplet approach (HR 0.64, 95% CI 0.52, 0.78, p<0.0001).
Conclusion(s): KCRD was well tolerated with deep responses pre- and post-transplant and a significant PFS benefit compared to triplet therapy across all risk groups. Keywords: carfilzomib carfilzomib-lenalidomide-dexamethasone Lenalidomide Tracks: Treatment of Newly Diagnosed Myeloma Transplant Eligible
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The iliac crest is the sampling site for minimal residual disease (MRD) monitoring in multiple myeloma (MM). However, the disease distribution is often heterogeneous, and imaging can be used to complement MRD detection at a single site. We have investigated patients in complete remission (CR) during first-line or salvage therapy for whom MRD flow cytometry and the two imaging modalities positron emission tomography (PET) and diffusion-weighted magnetic resonance imaging (DW-MRI) were performed at the onset of CR. Residual focal lesions (FLs), detectable in 24% of first-line patients, were associated with short progression-free survival (PFS), with DW-MRI detecting disease in more patients. In some patients, FLs were only PET positive, indicating that the two approaches are complementary. Combining MRD and imaging improved prediction of outcome, with double-negative and double-positive features defining groups with excellent and dismal PFS, respectively. FLs were a rare event (12%) in first-line MRD-negative CR patients. In contrast, patients achieving an MRD-negative CR during salvage therapy frequently had FLs (50%). Multi-region sequencing and imaging in an MRD-negative patient showed persistence of spatially separated clones. In conclusion, we show that DW-MRI is a promising tool for monitoring residual disease that complements PET and should be combined with MRD.

The emergence of treatment resistant sub-clones is a key feature of relapse in multiple myeloma. Therapeutic attempts to extend remission and prevent relapse include the maximisation of response and use of maintenance therapy. We used whole exome sequencing to study the genetics of paired presentation and relapse samples from 56 newly diagnosed patients, following induction therapy, randomised to receive either lenalidomide maintenance or observation as part of the Myeloma XI trial. Patients included were considered high risk, relapsing within 30 months of maintenance randomisation. Patients achieving a complete response had predominantly branching evolutionary patterns leading to relapse, characterised by a greater mutational burden, an altered mutational profile, bi-allelic inactivation of tumour suppressor genes, and acquired structural aberrations. Conversely, in patients achieving a partial response the evolutionary features were predominantly stable with a similar mutational and structural profile. There were no significant differences between patients relapsing after maintenance lenalidomide vs observation. This study shows that the depth of response is a key determinant of the evolutionary patterns seen at relapse.

Background: Carfilzomib is a second-generation irreversible proteasome inhibitor that has shown significant efficacy in phase III studies of relapsed myeloma patients. The UK NCRI Myeloma XI study is the first phase III randomised study that has reported outcomes for the use of carfilzomib as induction therapy in newly diagnosed myeloma patients prior to autologous stem cell transplant (ASCT). The KCRD combination deepened responses and prolonged progression-free survival compared to response adapted immunomodulatory agent-based triplet +/-proteasome inhibitor-based triplet therapy (Jackson GH et al, ASH 2018).
Aim(s): In this exploratory analysis we examine the efficacy of KCRD compared to triplet therapy across different molecular subgroups within the Myeloma XI trial.
Method(s): 1056 patients were randomised between KCRD (28 day cycles of carfilzomib (K) 36 mg/m² IV d1-2, 8-9, 15-16 (20 mg/m² #1d1-2), cyclophosphamide (C) 500 mg PO d1,8, lenalidomide (R) 25 mg PO d1-21, dexamethasone (D) 40 mg PO d1-4,8-9,15-16) and triplet CTD/CRD prior to ASCT. Patients who received CTD/CRD underwent response-adapted intensification for suboptimal responders with a randomization to proteasome inhibitor (bortezomib, CVD) containing triplet or no further therapy. A maintenance randomisation at 3 months post ASCT compared lenalidomide to observation. Molecular analysis was available for a representative subset of patients (n = 339). High-risk (HiR) was classified in the study as the presence of t(4;14), t(14;16), t(14;20), del(17p) or gain(1q) and ultra-high risk (UHiR) the presence of two or more lesions. Exploratory analyses of outcome by individual molecular risk lesion and by HiR defined without the inclusion of gain(1q) and t(14;20) were also performed. Efficacy analyses included PFS and response.
Result(s): KCRD was associated with a significantly longer PFS than triplet therapy for the whole population, with no significant heterogeneity between risk groups (standard risk (SR) hazard ratio (HR) 0.55, 95%CI 0.33, 0.92, median PFS KCRD NR vs CTD/CRD 36 months), HiR (HR 0.68, 95%CI 0.40, 1.19, median PFS KCRD NR vs CTD/CRD 37 months) and UHiR (HR 0.72, 95%CI 0.26, 2.02, median PFS KCRD 25 vs CTD/CRD 20 months, phet = 0.7841). For patients receiving KCRD there was no difference in response rate at the end of induction 1 by risk group (> = VGPR: SR 86.0%, HiR 87.0% and UHiR 88.2%). However, UHiR disease was associated with significantly shorter PFS than both SR (p = 0.0073) and HiR (p = 0.0180) whilst there was no significant difference in outcome between patients with HiR (only one adverse lesion) and SR (p = 0.7213). Within groups of patients with each HiR lesion there was a benefit for KCRD over CTD/CRD. The lowest hazard ratio was observed in patients with a del(17p), (HR 0.12, 95%CI 0.03, 0.51, median PFS KCRD 38 vs CTD/CRD 17 months). When HiR was defined only by the presence of t(4;14), t(14;16) and/or del(17p) there remained a significant benefit for KCRD over CTD/CRD (HiR: HR 0.38, 95%CI 0.19, 0.77, median PFS KCRD 38 vs CTD/CRD 22 months, SR: HR 0.58, 95%CI 0.39, 0.88, median PFS KCRD NR vs CTD/CRD 38 months) with no heterogeneity of effect identified between risk groups. Summary/Conclusion: KCRD is associated with prolonged PFS compared with response-adapted triplet therapy across all molecular risk subgroups, however these are defined. Even with the highly effective quadruplet combination KCRD, UHiR patients continue to have significantly worse outcomes than patients with standard risk disease and there remains an unmet need for novel therapeutic approaches for these patients